Regal (rgal), a.
Etymology: [L. regalis, fr. rex, regis, a king. See Royal, and cf. Rajah, Realm, Regalia.]
Of or pertaining to a king; kingly; royal; as, regal authority, pomp, or sway. "The regal title." Shak. He made a scorn of his regal oath. Milton.
Syn. -- Kingly; royal. See Kingly.
1 other Webster entry under this spelling
Regal, n.
(Mus.)
A small portable organ, played with one hand, the bellows being worked with the other, -- used in the sixteenth and seventeenth centuries.
Shades of meaning
Fernald has no entry of its own for regal; he lists it under royal.
Where he writes about it:
Regal denotes that which in outward state is appropriate for a king; a subject may assume regal magnificence in residence, dress, and equipage. — from royal
Princely is especially used of treasure, expenditure, gifts, etc., as princely munificence, a princely fortune, where regal could not so well be used and royal would change the sense. — from royal